This invention relates generally to a gear pump and, more particularly, to a gear pump which is especially adapted to supply pressurized liquid fuel to an oil burner. Gear pumps of this general type are disclosed in Harwath U.S. Pat. No. 4,171,939 and Hunsberger et al U.S. Pat. No. 4,391,580.
In such a gear pump, it is conventional for a pinion gear to be secured by a key to the free end portion of a rotatable drive shaft having a free end which normally is disposed in spaced opposing relation with an end plate. Also, it is conventional to stake the key in the shaft by deforming the metal of the free end of the shaft with a hot upsetting operation. As a result of the upsetting operation, burrs protrude axially from the free end of the shaft.
Under abnormal conditions, the drive shaft may be rammed toward the end plate with sufficient force to cause the burrs to embed in the end plate. If this occurs, the shaft may lock up and render the pump useless.